1. Field
This application relates generally to wireless communication, and more specifically, to distance-based functionality in a wireless communication system.
2. Background
In a wireless communication system various provisions may be made to enable two or more wireless devices to communicate with one another and, in some applications, to enable one wireless device to access functionality provided by another wireless device. For example, when a wireless device enters a coverage area of another wireless device, the wireless devices may perform an association operation to enable the two devices to communicate with one another. In addition, other related operations such as presence management may be performed to enable a wireless device to affect the operation of another wireless device.
Examples of association include setting up a wireless laptop and an wireless access point to communicate or setting up communication between a wireless cell phone or entertainment device (e.g., an MP3 player) and a peripheral device such as a wireless headset (e.g., headphones, an ear piece, etc.) or watch. Briefly, association may involve exchanging messages that enable the wireless devices to determine whether they are capable of communicating with one another and whether they are authorized to do so. For example, the wireless devices may exchange messages that indicate their respective capabilities. In conjunction with this procedure, the wireless devices may negotiate or cooperate in some other manner to agree on a set of parameters to be used for communicating. Moreover, in some applications the wireless devices may utilize an authentication procedure of some type to verify the identity of each other. This identity information may be used by the wireless devices to, for example, determine whether they are authorized to communicate with one another.
Various operations may be performed to enable or otherwise facilitate association. For example, some applications may employ signal strength-based association where it is assumed that the wireless devices are close enough to associate if a received signal strength exceeds a threshold. Other applications may employ RFID-related technology whereby wireless devices are allowed to associate with another if they are close enough so that one device induces RF energy in another device.
In some applications a wireless device may employ presence management to provide certain functionality based on the proximity of the wireless device to another device. For example, in some applications presence management may be employed to modify a user interface of a computer based on which user is sitting in front of the computer. Presence management also may be used to modify the characteristics of a room (e.g., lighting, temperature, music, etc) based on who is in the room.
In practice, an operation such as association or presence management may involve some user interaction with the wireless device to initiate or complete the operation. For example, during association a user may manually set each wireless device into an association or discovery mode, navigate through some software interfaces to a list of discovered wireless devices, select a wireless device, and potentially input some information about the wireless device. In a typical example, information to be entered by a user may include authentication codes or multiple access code information. Similarly, during presence management a user may press a configuration button (e.g., associated with a car seat, a home theater system, etc.), type in a username and password, insert a card, or invoke wireless detection of the presence of a device.
In practice, operations such as association and presence management may not provide a desired level of functionality or may be inconvenient for a user. For example, presence management may be relatively course in nature in that it simply involves determine whether a connection with another wireless device may be detected. In addition, the steps performed by a user to accomplish association, presence management, or other operations (e.g., as mentioned above) may be relatively complicated and confusing for the user. Consequently, a need exists for alternative methods for performing such operations.